DIY Rifle: We Interview the Man Behind the 3D-Printed Gun "Grizzly"

After he fired the first working 3D printed plastic handgun, Texas law student and Defense Distributed founder Cody Wilson inspired others to create their own firearms. An anonymous young Canadian who goes by a few online handles ("CanadianGunNut" and "ThreeD Ukulele," or just "Matthew") designed and printed from ABS-plus plastic a rifle he called the Grizzly. The rifle did not perform so well when first test-fired on July 23—the gun's barrel and receiver split after discharging the first round. But Matthew is now back with Grizzly Version 2.0, which has a thicker, tapered barrel.

When did you get interested in designing guns?

I work for a company that makes tools related to the construction industry, and about six years ago, a coworker showed me some of his hunting rifles. I thought their construction was fascinating and I ended up getting my license within a few months of handling a real gun for the very first time.

What about 3D printing?

I got into 3D printing, also through my work, in May. I learned Solidworks, the program I used to design the Grizzly, through a month-long introductory course online. It gave me a great basis to work from, and I found that the more stuff I drew, the more learned.

Advertisement - Continue Reading Below

Why did you print the Grizzly rifle?

I printed the Grizzly as a personal and technical challenge. The inspiration came from the work Cody Wilson and Defense Distributed did with AR-15 lower receivers and the Liberator pistol.

Is the Grizzly rifle actually rifled?

The barrel of Grizzy 1.0 was a smooth bore. Version 2.0 has a rifled bore, though the bullet barely touches it as it shoots out. I believe the rifling would melt or get destroyed if it were designed to the exact specs of a real bore. Another difference between the two rifles is that 2.0's barrel is 50 percent larger.

Most Popular

Did you get professional feedback on your designs?

I don't know if I would call it professional feedback, but I did receive a lot of feedback on the design process I posted on the DEFCAD forum [associated with Wilson's Defense Distributed] and a Canadian gun forum. Some ideas I have tried and some not, and some I intend to try.

Was it difficult to get the Grizzly to fire?

Getting the rifle to work was really just trial and error. The first issue was light primer strikes, so I had to alter the geometry of the hammer and trigger. Next, I tried an acetone treatment to smoothen out the bore. I don't know what I did wrong, but I nearly melted it! Finally, the barrel of Grizzly 1.0 ended up cracking because it was too small.

What do you have planned for the future?

I may try a semiautomatic gun, but I will first need to solve the issue of hot bullet casings melting the plastic in the chamber. I may try either a full liner or a smaller chamber liner; people on the forums have been suggesting both. I was also thinking about replaceable 3D-printed liners to cut down on barrel costs.

Is this just a hobby, or could the open sourcing of 3D designs affect the gun industry?

I could see the 3D printing guns leading to new designs from major manufacturers, but only once the technology gets a little better. For now, I really see it as a hobbyist tool.